59 lines
1.8 KiB
Plaintext
59 lines
1.8 KiB
Plaintext
BOSCH BMM150 3-axis magnetic sensor
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The BOSCH 3-axis magnetic sensor is a complete 3-axis magnetic sensor with
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on-chip signal processing and intergrated i2c bus. It can be connected to host
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processor via i2c. It can measure magnetic fields within the full scale range
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from -16 Gauss to +16 Gauss.
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Required properties:
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- compatible : Should be "bosch,bmm150".
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- reg : i2c address of the device.
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- vdd-supply : Analog power supply needed to power up the device.
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- vio-supply : Digital IO power supply needed for IO and I2C.
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- bmm,dir : String value of the direction of the ecompass sensor
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chip. There are 8 patterns of direction:
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x > 0 /___________o
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/ /|
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/ / |* 1st pin is here
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/________/ /|
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|_______/|/ |/ z > 0
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/
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|/ y > 0
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The above graph shows the coordination of the sensor chip. Specify the
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following string to bosch,dir to convert it into Android coordination.
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Note the definition of sensor placement on target board is relative to
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Android portrait mode.
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left right up down
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obverse-x-axis-forward Y+ Y- X+ X-
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obverse-x-axis-rightward X- X+ Y+ Y-
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obverse-x-axis-backward Y- Y+ X- X+
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obverse-x-axis-leftward X+ X- Y- Y+
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reverse-x-axis-forward Y- Y+ X+ X-
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reverse-x-axis-rightward X- X+ Y- Y+
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reverse-x-axis-backward Y+ Y- X- X+
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reverse-x-axis-leftward X+ X- Y+ Y-
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Optional properites:
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- bmm,auto-report : Boolean value to enable auto-report mode.
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Example:
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A chip on 8916 platform with the pattern as the above graph:
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&i2c_0 { /* BLSP1 QUP2 */
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bosch@12 {
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compatible = "bosch,bmm150";
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reg = <0x12>;
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vdd-supply = <&pm8916_l17>;
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vio-supply = <&pm8916_l6>;
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bmm,dir = "obverse-x-axis-forward";
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bmm,auto-report;
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};
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};
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